An oil or gas well for extracting fluids such as petroleum oil hydrocarbons from a subterranean formation can include one or more subsurface safety valves for restricting fluid flow from the well. Subsurface safety valves are used to close off a well. For example, a well may be closed in the event of an uncontrolled condition to ensure the safety of surface personnel and prevent property damage and pollution.
A spring-loaded retention mechanism for closing a subsurface safety valve may exert sufficient force to overcome downhole forces exerted by fluids in the wellbore at depths thousands of feet below sea level. Increasing the deployment depth for the subsurface safety valve can require the use of springs exerting correspondingly larger forces. Hydraulic control systems for actuating the subsurface safety valve require a control line pressure sufficient to overcome the force exerted by the spring-loaded retention mechanism. Thus, increasing the depth at which the subsurface safety valve is deployed increases the amount of pressure required to open the closure mechanism.
Apparatuses and systems are desirable that can reduce the control line pressure requirements for a subsurface safety valve and increasing the depth at which the subsurface safety valve can be deployed.